Let-off mechanism.



W. STRITTMATTER & H. SCHIMMEL.

. LET-OFF MECHANISM. APPLICATION FILED SEPT. 1 1. ms.

1,230,235. Patented June 19, 1917.

w/msss;

lerman Schimmek WILLIAM STRITTMATTER AND LHERMAN SGI-IIMMEL, OF WEEHAWKEN, NEW JERSEY.

LET-OFF MECHANISM.

Application filed September 11, 1916.

To all whom it may concern:

Be it known that we, WILLIAM STRITT- MATTER and. HERMAN Sonnmmmcitizens of the United States, residing at Weehawken, in the county of Hudson and State of New Jersey, have invented certain new and useful Improvements in Let-Off Mechanisms, of which the following is a specification.

This invention relates to let-off mecha nisms for looms of the type in which a lever structure controls the braking medium and is itself controlled so as to change the braking pressure by the counter-acting influences of weights on, or the weight of, the lever structure to draw it downwardly and the tightening of the warp to pull it upwardly, and it consists in providing in place of the braking media now used in mechanisms of this class a braking medium which shall result in the letting off operation occurring always with equable or uniform yield of the warp-beam to the draft of the warp, thereby to avoid at times overstraining the warp and at others too suddenly releasing it and consequently producing so-called shiers and other imperfections in the woven cloth. We eliminate belts, bands, shoes and the like having long bearing surfaces as braking media, in the preferred construction, because they stick to the beams and result in unduly binding the beams followed by toosudden release thereof, which involves the overstraining and subsequent too-sudden relaxation of the warp, and give an action that is essentially jerky; and as the braking surface we provide convex means, formed of rubber or equivalent yielding material.

Our invention is herein illustrated in connection with a narrow-ware loom; but it is to be understood that it may be applied to looms for weaving broad goods.

In the accompanying drawing,

Figure 1 is a side elevation of a let-off unit, constructed in accordance with our invention, of a narrow ware loom, a part of the beam being shown in section; and,

Fig. 2 is a fragmentary plan view, certain parts being omitted.

a is a frame in which is journaled on a horizontal axis the warp beam 1) which, as usual, has peripherally grooved flanges or heads 0.

There is shown, pivotally connected to the frame a, a lever structure of well-known type including a long lever d fulcrumed to Specification of Letters Patent.

Patented June 19, 1917.

Serial No. 119,349.

the frame at one end and carrying weights 0 which tend to move the lever structure downwardly and also carrying, journaled on the spindle f, a roller 9, under which the.

warp A extends from the beam 6; said lever structure also includes a short lever 71, fulcrumed in the lever (l and adapted to bear downwardly against the same and having journaled therein on a spindle c" the roller 5 over which the warp A extends before extending under the roller 9.

In place of using a strap, band or the like connected on the one hand to the frame a and on the other to the lever (Z, according to the usual construction, we use the brake member y' shown in the drawing. This is a lever having one end upturned, as at k, and entered into a hole Z in a lug m which projects from one side of the frame a, and having its other end operatively connected with the lever 71;, asby a link a pivoted to said end of member 7' on the one hand and on the spindle 71 between lever h and the adjoining end of roller 2' (Fig. 2) on the other. In the preferred construction, the forward portion of member j is bent downwardly, as shown in Fig. 1, so that it tends to remain in a vertical plane and so-as to afford clearance for another let-off unit arranged above the one shown in the drawing.

The member j bears against the grooved periphery of the flange or head a of the beam, and in the preferred construction it includes a contact piece 0, suitably attached to the bar forming said member j and composed of rubber or other suitable yielding material; the acting face of this contact piece is convex, as shown, so as to afford a relatively limited contact with the periphery of the flange of the warp beam.

By our invention we not only obtain the desired equable release of the warp beam so necessary in order to produce woven cloth not possessing the imperfections hereinbefore alluded to, but can attain this result in existing looms by simply discarding their brake-bands or the like and substituting our member y We do not wish to be limited to the precise construction herein shown and described what we claim being:

1. A let-ofl mechanism for looms including a frame, a beam journaled therein on a horizontal axis, a gravity-actuated leverstructure fulcrumed in the frame also on ahorizontal axis, the Warp being adapted to engage said lever structure and move the same counter to gravity-action, and a brake member consisting of a lever extending over the beam and fulcrumed at one end in the frame and operatively connected at its other end with said lever structure and bearing against said beam between its ends.

2. A let-off mechanism for looms including a frame, a beam journaled therein on a horizontal axis, a gravity actuated lever structure fulcrumed in the frame also on a horizontal axis, the Warp being adapted to engage said lever structure and move the same counter to gravity-action, and a brakemember extending over the beam and having one end upturned and the other bent (1OWI1 Ward and connected With said lever structure, said member bearing against the beam between its ends, and the frame having an opening receiving and aifording a fulcrum bearing for the upturned end of said memher.

In testimony whereof We aflix our signatures.

WVILLIAM STRITTMATTER. HERMAN SCHIMMEL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

